Abstract: The present invention pertains to guide catheter exchange devices for exchanging a guide catheter advanced over a balloon catheter and a coronary guide wire without removing the coronary guide wire in percutaneous transluminal coronary angioplasty. In one embodiment, the invention pertains to a guide catheter exchange device for exchanging a guide catheter employed by a over-the-wire balloon catheter. In this embodiment, the exchange device comprises Section 1, Section 2, and a connecting device for connecting Section 1 and Section 2. Section 1 is a hollow wire having a soft tip, an inner diameter from about 0.012 inches to about 0.020 inches, an outer diameter from about 0.030 inches to about 0.040 inches, and a length from about 120 centimeters to about 160 centimeters. Section 2 is a hollow coiled wire having an inner diameter from about 0.012 inches to about 0.020 inches, an outer diameter from about 0.030 inches to about 0.040 inches, and a length from about 120 centimeters to about 160 centimeters.